5M2100 – EcoBoost Mustang Catback Exhaust

Mustang EcoBoost 2015 - 2019

Congratulations on your purchase of the COBB Tuning EcoBoost Mustang Catback Exhaust! The following instructions will assist you through the installation process. Please read them BEFORE beginning the install to familiarize yourself with the steps and tools needed. If you feel you cannot properly perform this installation, we HIGHLY recommend you take the vehicle to a qualified and experienced automotive technician.

Parts List

COBB Mustang Ecoboost Cat-Back Exhaust
(6) Flange Bolts
(6) Flange Nuts
(3) Gaskets

Tools Needed

Phillips head screwdriver
Flathead screwdriver
3/8" ratchet
3/8" 13mm socket
3/8" 15mm socket

Stock Catback Removal

With the car parked in a flat level area, jack it up and safely support it.
Allow the car to cool down
Using a jack or other item, support the catback as it is large and one piece. Now remove the front attaching point to the downpipe
Remove the front hanger and loosen up the front exhaust clamp using a 15mm socket.
Use a 13mm wrench to remove the bolts holding the stock catback to the car. These are located right behind the rear differential, towards the back of the car.

It is recommended that TWO people are used to remove the catback for safety as it is a large heavy piece.
Once the bolts are removed, lift up on each exhaust hanger to "unclip" them from the vehicle.
Pull the catback towards the front of the car to remove the remaining two hanger rods from the exhaust hangers within the rear bumper.
Keep the bolts and hangers as they will be used for the installation of the COBB parts.

COBB Catback Installation

Installation of COBB Downpipe and Catback

Take the two rubber exhaust hangers you removed previously as seen in step 8 and place on the COBB catback in the respective positions.
Take the driver's side muffler section (shown via the top arrow in the photo above) and install into the drivers side rear exhaust hanger. Then clip the front exhaust hanger into the stock mounting position. Loosely install the hanger bolt but don't tighten.
For the passenger's side muffler section, insert the hanger rod into the rear exhaust hanger. Then clip the front exhaust hanger into the stock mounting position. Loosely install the hanger bolt but don't tighten.
Now install the Y-pipe section of the exhaust using two (2) of the M8 exhaust bolts, two (2) 8mm nuts and one (1) of the gaskets provided in the COBB kit where it connects to each muffler assembly. Use two 14mm wrenches to tighten the nuts onto the bolts. Do not completely tighten! Make sure the "COBB" logo is orientated correctly (upright)!
Once every part is in the correct place, begin tightening all nuts and bolts from the turbo studs back to the catback. Line up each exhaust flange and adjust as necessary to ensure the exhaust tips are placed to your preference. Make sure to tighten down the hanger bolts above the rear differential as well! It helps to center the exhaust in the bumper outlets before tightening the hanger bolts.
Wipe the exhaust down with brake cleaner and a lint-free rag in order to remove any fingerprints, otherwise they will burn into the metal and become permanent.
With everything in place and tightened drop the car down and start it up to check for exhaust leaks.